Fair Value Measurements - Schedule of Fair Value and Amortized Cost of Investments in Marketable Securities by Major Security Type (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	$ 682,559	$ 735,042
Unrealized Gain	4	57
Unrealized Loss	(1,265)	(13)
Fair Value	681,298	735,086
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	147,914	146,468
Fair Value	147,914	146,468
U.S. Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	112,473	301,075
Unrealized Gain	1	38
Unrealized Loss	(304)	(1)
Fair Value	112,170	301,112
U.S. Government Agency Obligations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost		24,997
Unrealized Gain		4
Fair Value		25,001
Corporate Securities and Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	422,172	262,502
Unrealized Gain	3	15
Unrealized Loss	(961)	(12)
Fair Value	$ 421,214	$ 262,505